package mylist;

import java.util.Arrays;

public class MyArrayList implements IList{
    public int[] elem;
    public int usedSize;

   public static final int DEFAULT_SIZE = 10;

    public MyArrayList(){
        this.elem = new int[ DEFAULT_SIZE];
    }
    public MyArrayList(int capacity){
        this.elem = new int[capacity];
    }

    @Override
    public void add(int data) {
         checkCapacity();
         this.elem[this.usedSize] = data;
         this.usedSize++;
    }
    private void checkCapacity(){
        if(isFull()){
            //扩容
            elem = Arrays.copyOf(elem,elem.length*2);
        }
    }
    @Override
    public void add(int pos, int data) {
        try {
            checkPosOnAdd(pos);
        }catch (PosILLegality e){
            e.getStackTrace();
            return;
        }
        checkCapacity();
        for(int i = usedSize-1;i>=pos;i--){
            elem[i+1]=elem[i];
        }
        elem[pos] = data;
        usedSize++;
    }
    private void checkPosOnAdd(int pos)throws PosILLegality{
        if(pos<0&&pos>usedSize){
            System.out.println("不符合法");
            throw new PosILLegality("插入元素下标异常"+pos);
        }
    }
    @Override
    public boolean contains(int toFind) {
            if(isEmpty()){
                return false;
            }
            for(int i = 0;i<usedSize;i++){
                if(elem[i]==toFind){
                    return true;
                }
            }
            return false;
    }

    @Override
    public int indexOf(int toFind) {
        if(isEmpty()){
            return -1;
        }
        for(int i = 0;i<usedSize;i++){
            if(elem[i]==toFind){
                return i;
            }
        }
        return -1;
    }

    @Override
    public int get(int pos) throws MyArrayListEmpty{
        checkPosOnGetAndSet(pos);
        if(isEmpty()){
            throw new MyArrayListEmpty("获取指定下标元素时"+"顺序表位空");
        }
        return elem[pos];
    }

    private void checkPosOnGetAndSet(int pos) throws PosILLegality {
        if (pos < 0 || pos >= usedSize) {
            System.out.println("不符合法");
            throw new PosILLegality("获取制定下标的元素异常" + pos);

        }
    }

    @Override
    public void set(int pos, int value) {
            checkPosOnGetAndSet(pos);
            elem[pos]=value;
    }

    @Override
    public void remove(int toRemove) {
        int index = indexOf(toRemove);
        if(index==-1){
            System.out.println("没有这个数字");
            return;
        }
        for(int i =index;i<usedSize-1;i++){
            elem[i]=elem[i+1];
        }
        usedSize--;
    }

    @Override
    public int size() {
        return this.usedSize;
    }

    @Override
    public void clear() {
            this.usedSize=0;
    }

    @Override
    public void display() {
        for(int i = 0;i<this.usedSize;i++){
            System.out.println(this.elem[i]+" ");
        }
        System.out.println();
    }

    @Override
    public boolean isFull() {
        return usedSize==elem.length;
    }

    @Override
    public boolean isEmpty() {
        return false;
    }
}
